@Ton bro just look at these colors. he needs to look at some basic pixel art tutorials.The details are stunning in some sprites but it gets kind of cluttered on smaller sprites. The colors needs to be heavily worked on, along with the anti-aliasing, which is pretty 'banded' if you look closer at it.

Shading is quite dirty and the colors are ugly and poluted.You really should try looking at palette tutorials. Using HUE shifting and changing the saturation makes the shades looks better than just darkening the colors like you did.